The incidence and the risk of pneumothorax and chest tube placement after percutaneous CT-guided lung biopsy: The angle of the needle trajectory is a novel predictor

Study objective: Pneumothorax remains the most common complication of percutaneous CT-guided lung biopsy, despite improved techniques. The rate of pneumothorax reported in the literature ranges from 19 to 60%. The aims of this study were to estimate the risk of pneumothorax in patients undergoing CT-guided lung biopsy, and to determine which factors affect its occurrence. Design: Retrospective study. Patients and methods: This study involved 289 consecutive patients who underwent biopsy in our hospital under consistent methods, using only one type of needle, the 19-gauge Tokyo Medical College (TMC) Needle (Takei; Tokyo, Japan), under CT guidance. Result: Seventy-seven patients (26.6%) had pneumothorax after percutaneous CT-guided lung biopsy. Forty-one of the 77 patients (53.2%) who had pneumothorax (14.2% of the entire series) required placement of a chest tube. Our present study, using multivariate logistic regression analysis, confirmed that greater lesion depth, wider trajectory angle, and increasing FVC percent predicted are independent risk factors of pneumothorax, and that two former factors are independent risk factors of chest tube placement following percutaneous CT-guided lung biopsy. Conclusions: The angle of needle route is a novel predictor of this complication. Our findings suggest that low pneumothorax rates are achieved by combining several techniques to reduce the risk of pneumothorax.